<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="../../bootstrap/css/bootstrap.min.css">
</head>
<body>
    <button class="btn">按钮</button>
    <button class="btn btn-primary">按钮</button>
    <button class="btn btn-info">按钮</button>
    <button class="btn btn-success">按钮</button>
    <button class="btn btn-warning">按钮</button>
    <button class="btn btn-danger">按钮</button>

    <input type="text" class="form-control" placeholder="请填写">
</body>
</html>